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951.
Objective--To evaluate whether electroencephalography (EEG) recovery could be considered a reliable marker of brain injury after experimental hypothermic circulatory arrest (HCA). Design--Cortical electrical activity was registered before and after a 75-min period of HCA in 27 pigs that survived 7 days after the experiment. The sum of EEG bursts was counted as a percentage of the sum of artifact-free bursts and suppressions, and this percentage was used as a measure of EEG activity in the analysis. Results--Brain infarction developed in 13 animals (48.1%), in 12 cases (44.4%) having involved the cortex, in 1 case the thalamus (3.7%) and in another the hippocampus (3.7%). The mean EEG burst percentage significantly correlated with the total brain histopathological score (ρ?=??0.588, P?=?0.001). EEG burst percentage from the 2?h 20?min to the 7?h 20?min interval correlated with the total brain histopathological score and with the cortex, brainstem and cerebellum scores. The mean EEG burst percentage rate was higher, but not significantly, among the animals without brain infarction (38.5% vs 32.4%), but such a difference was significant at the 3?h 20?min postoperative interval (P?=?0.02). The mean EEG burst percentage significantly correlated with brain glucose concentration at the 1?h interval (ρ?=?0.387; P?=?0.046), brain lactate concentration at the 2?h interval (ρ?=??0.431; P?=?0.025), and the brain lactate/glucose ratio at the 1?h 30?min interval from the start of rewarming (ρ?=??0.433; P?=?0.024). Conclusion--A decreased EEG burst percentage seems to be associated with an increased risk of developing histologically evident brain ischemic injury in the cortex, brainstem and cerebellum after experimental HCA.  相似文献   
952.
思者女,57岁,务农.主诉:头痛、恶心伴呕吐半个月.患者半个月前头痛伴恶心发作,开始误认为感冒,进行治疗后效果不佳,随后出现喷射状呕吐,在当地农村卫生所给予甘露醇治疗后症状略有减轻.因高颅压症状持续加重到当地县医院就诊,头颅CT示左颞肿瘤.为进一步治疗,患者于2006年11月12日入住我院.入院后进行抽血、心电图、胸片检查,术前诊断:颅内占位性病变,考虑为脑肿瘤.3d后在气管插管全麻下行开颅手术,左颞入路,术中发现左侧颞中回至颞极之间脑组织呈黄绿色质变,有包膜,质地略硬,即考虑脑脓肿可能,先行穿刺,抽出黄绿色脓液约30 mL,初步诊断为铜绿假单胞菌感染、脑脓肿.  相似文献   
953.
INTRODUCTIONliver transplantation can be the only treatment for acute liver failure.PRESENTATION OF CASEA 59 year-old female patient with acute liver failure due to mushroom poisoning underwent auxiliary liver transplantation. The liver graft was harvested from a brain-dead donor with a deep gunshot wound in the posterior sector of the graft. The postoperative course was uneventful with rapid recovery of the recipient and no complications associated with the gunshot wound.DISCUSSIONPatients scheduled for urgent liver transplantation should have rapidly a liver graft otherwise the mortality rate is high. In our case, an injured liver graft by gunshot was successfully used allowing liver transplantation and increasing the pool of liver grafts.CONCLUSIONA gunshot liver graft can be used if the major vascular or biliary structures are not injured.  相似文献   
954.
Most of the commonly used antidepressants block monoamine reuptake transporters to enhance serotonergic or noradrenergic neurotransmission. Effects besides or downstream of monoamine reuptake inhibition are poorly understood and yet presumably important for the drugs' mode of action. In the present study we aimed at identifying hippocampal cellular pathway alterations in DBA/2 mice using paroxetine as a representative Selective Serotonin Reuptake Inhibitor (SSRI). Furthermore we identified biomarker candidates for the assessment of antidepressant treatment effects in plasma. Hippocampal protein levels were compared between chronic paroxetine- and vehicle-treated animals using in vivo15N metabolic labeling combined with mass spectrometry. We also studied the time course of metabolite level changes in hippocampus and plasma using a targeted polar metabolomics profiling platform. In silico pathway analyses revealed profound alterations related to hippocampal energy metabolism. Glycolytic metabolite levels acutely increased while Krebs cycle metabolite levels decreased upon chronic treatment. Changes in energy metabolism were influenced by altered glycogen metabolism rather than by altered glycolytic or Krebs cycle enzyme levels. Increased energy levels were reflected by an increased ATP/ADP ratio and by increased ratios of high-to-low energy purines and pyrimidines. In the course of our analyses we also identified myo-inositol as a biomarker candidate for the assessment of antidepressant treatment effects in the periphery. This study defines the cellular response to paroxetine treatment at the proteome and metabolome levels in the hippocampus of DBA/2 mice and suggests novel SSRI modes of action that warrant consideration in antidepressant development efforts.  相似文献   
955.
Hippocampal sclerosis (HS) is the most frequent histopathology encountered in patients with drug‐resistant temporal lobe epilepsy (TLE). Over the past decades, various attempts have been made to classify specific patterns of hippocampal neuronal cell loss and correlate subtypes with postsurgical outcome. However, no international consensus about definitions and terminology has been achieved. A task force reviewed previous classification schemes and proposes a system based on semiquantitative hippocampal cell loss patterns that can be applied in any histopathology laboratory. Interobserver and intraobserver agreement studies reached consensus to classify three types in anatomically well‐preserved hippocampal specimens: HS International League Against Epilepsy (ILAE) type 1 refers always to severe neuronal cell loss and gliosis predominantly in CA1 and CA4 regions, compared to CA1 predominant neuronal cell loss and gliosis (HS ILAE type 2), or CA4 predominant neuronal cell loss and gliosis (HS ILAE type 3). Surgical hippocampus specimens obtained from patients with TLE may also show normal content of neurons with reactive gliosis only (no‐HS). HS ILAE type 1 is more often associated with a history of initial precipitating injuries before age 5 years, with early seizure onset, and favorable postsurgical seizure control. CA1 predominant HS ILAE type 2 and CA4 predominant HS ILAE type 3 have been studied less systematically so far, but some reports point to less favorable outcome, and to differences regarding epilepsy history, including age of seizure onset. The proposed international consensus classification will aid in the characterization of specific clinicopathologic syndromes, and explore variability in imaging and electrophysiology findings, and in postsurgical seizure control.  相似文献   
956.
Brain water self diffusion was investigated by magnetic resonance scanning in 7 patients fulfilling conventional diagnostic criteria for pseudotumour cerebri. Quantitative diffusion measurements were obtained using single spin echo pulse sequences with pulsed magnetic field gradients of different magnitude. In all patients the diffusion images showed an increased diffusion in various brain regions when compared with the diffusion coefficients for corresponding regions in healthy subjects. In 3 pseudotumour patients the increased self diffusion was localized to the periventricular regions, while 4 patients had increased diffusion in the whole brain. The findings indicate the presence of increased brain water content both intra- and extracellularly suggesting that patients with pseudotumour have two defects of pathogenetical significance: intracellular water accumulation and increased resistance to cerebrospinal fluid (CSF) outflow leading to an interstitial oedema.  相似文献   
957.
Pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) act through three class B G-protein coupled receptors, PAC1, VPAC1 and VPAC2, initiating multiple signaling pathways. In addition to natural peptides ligands, a number of synthetic peptides and a small molecular antagonist have been generated. Genetically modified animals have been produced for the neuropeptides and receptors. Neuroanatomical, electrophysiological, behavioral and pharmacological characterization of the mutants and transgenic mice uncovered diverse roles of PACAP-PAC1-VAPC2 signaling in peripheral tissues and in the central nervous system. Human genetic studies suggest that the PACAP-PAC1-VPAC2 signaling can be associated with psychiatric illness via mechanisms of not only loss-of-function, but also gain-of-function. For example, a duplication of chromosome 7q36.3 (encoding the VPAC2 receptor) was shown to be associated with schizophrenia, and high levels of PACAP-PAC1 signaling are associated with posttraumatic stress disorder. Whereas knockout animals are appropriate to address loss-of-function of human genetics, transgenic mice overexpressing human transgenes in native environment using artificial chromosomes are particularly valuable and essential to address the consequences of gain-of-function. This review focuses on role of PACAP and PAC1 receptor in brain development, behavior of animals and potential implication in human neurodevelopmental disorders. It also encourages keeping an open mind that alterations of VIP/PACAP signaling may associate with psychiatric illness without overt neuroanatomic changes, and that tuning of VIP/PACAP signaling may represent a novel avenue for the treatment of the psychiatric illness.  相似文献   
958.

Background

Patients with acute deep vein thrombus (DVT) can safely be treated as outpatients. However the role of outpatient treatment in patients diagnosed with a pulmonary embolism (PE) is controversial. We sought to determine the safety of outpatient management of patients with acute symptomatic PE.

Materials and Methods

A systematic literature search strategy was conducted using MEDLINE, EMBASE, the Cochrane Register of Controlled Trials and all EBM Reviews. Pooled proportions for the different outcomes were calculated.

Results

A total of 1258 patients were included in the systematic review. The rate of recurrent venous thromboembolism (VTE) in patients with PE managed as outpatients was 1.47% (95% CI: 0.47 to 3.0%; I2: 65.4%) during the 3 month follow-up period. The rate of fatal PE was 0.47% (95% CI: 0.16 to 1.0%; I2: 0%). The rates of major bleeding and fatal intracranial hemorrhage were 0.81% (95% CI: 0.37 to 1.42%; I2: 0%) and 0.29% (95% CI: 0.06 to 0.68%; I2: 0%), respectively. The overall 3 month mortality rate was 1.58% (95% CI: 0.71 to 2.80%; I2: 45%). The event rates were similar if employing risk stratification models versus using clinical gestalt to select appropriate patients for outpatient management.

Conclusions

Independent of the risk stratification methods used, the rate of adverse events associated with outpatient PE treatment seems low. Based on our systematic review and pooled meta-analysis, low-risk patients with acute PE can safely be treated as outpatients if home circumstances are adequate.  相似文献   
959.
Sixteen patients with a megadolichobasilar artery and acute cerebrovascular symptoms are reported. All were explored by computerized tomography and vertebral angiography. Nine had transient ischaemic attacks or definitive ischaemic lesions, whereas 7 had subarachnoid or intracerebral haemorrhage. Among the patients with ischaemic troubles, vertebro-basilar insufficiency and pontine infarction were the most common clinico-radiological findings. Among the patients with intracranial haemorrhage, 4 had associated aneurysms or arteriovenous malformations, while 3 had subarachnoid or intracerebral haemorrhage with no vascular malformations on the angiograms. The possible relationships between the megadolichobasilar anomaly and the cerebral ischaemic or haemorrhagic pathologies are discussed also from a review of the pertinent literature.  相似文献   
960.
Abstract

The correlation of clinical with psychological and social data is an attempt to find predictors of the definite long term outcome after brain injury. 34 patients were reexamined 3 to 8 years after the accident using a number of psychological tests. Additionally, life quality was defined and evaluated. Only patients with an initial Glasgow Coma Scale-Score of 3–12, an intracranial traumatic lesion on computertomography and age 16–65 years at the time of accident were included in this study. Patients exhibited a uniform pattern of disturbances in psychosocial long term outcome. These disturbances were compared with initial clinical data: memory, attention and learning were significantly correlated with the duration of coma and the presence of additional extracerebraI injuries. From the initial computerized tomography, the findings 'compression of basal cisterns' and lintracerebral contusion' showed to be predictors of the cerebral function. Late social status and behavior, defined as quality of life, were clearly related with initial clinical findings. In conclusionl there are early clinical predictors of the long term social and psychological outcome after brain injury. [Neural Res 1997; 19: 305–310]  相似文献   
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